Insist on minimal pyproject.toml file

Change-Id: I9e8a134067593c393cff063b6c02a40afdd18c89
Signed-off-by: Stephen Finucane <stephenfin@redhat.com>

openstack_requirements/project.py

@@ -123,6 +123,35 @@ def _read_setup_cfg_extras(root: str) -> dict[str, list[str]] | None:
     return result
 
 
+def verify_pyproject_toml(root: str) -> bool:
+    data = _read_pyproject_toml(root)
+
+    if data is None:
+        print('Missing pyproject.toml file', file=sys.stderr)
+        return False
+
+    if 'build-system' not in data:
+        print("pyproject.toml is missing 'build-system' table", file=sys.stderr)
+        return False
+
+    if (build_backend := data['build-system'].get('build-backend')) != 'pbr.build':
+        print(
+            f"pyproject.toml has invalid 'build-system.build-backend'. "
+            f"Expected 'pbr.build'; got {build_backend!r}",
+            file=sys.stderr,
+        )
+        return False
+
+    if 'project' not in data:
+        print(
+            "pyproject.toml is missing 'project' table. This is not currently "
+            "an error but may be in the future",
+            file=sys.stderr,
+        )
+
+    return True
+
+
 class Project(TypedDict):
     # The root directory path
     root: str

openstack_requirements/tests/test_project.py

@@ -10,6 +10,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from io import StringIO
 import os
 import textwrap
 
@@ -56,6 +57,73 @@ class TestReadProject(testtools.TestCase):
         )
 
 
+class TestVerifyPyprojectToml(testtools.TestCase):
+    def setUp(self):
+        super().setUp()
+        self.stderr = StringIO()
+        self.useFixture(fixtures.MonkeyPatch('sys.stderr', self.stderr))
+
+    def test_valid(self):
+        root = self.useFixture(common.pep_518_fixture).root
+        self.assertTrue(project.verify_pyproject_toml(root))
+        self.assertEqual('', self.stderr.getvalue())
+
+    def test_missing_file(self):
+        root = self.useFixture(fixtures.TempDir()).path
+        self.assertFalse(project.verify_pyproject_toml(root))
+        self.assertEqual(
+            'Missing pyproject.toml file\n', self.stderr.getvalue()
+        )
+
+    def test_missing_build_system(self):
+        root = self.useFixture(fixtures.TempDir()).path
+        with open(os.path.join(root, 'pyproject.toml'), 'w') as fh:
+            fh.write(
+                textwrap.dedent("""
+                [project]
+                name = "foo"
+                """)
+            )
+        self.assertFalse(project.verify_pyproject_toml(root))
+        self.assertIn(
+            "pyproject.toml is missing 'build-system' table",
+            self.stderr.getvalue(),
+        )
+
+    def test_invalid_build_backend(self):
+        root = self.useFixture(fixtures.TempDir()).path
+        with open(os.path.join(root, 'pyproject.toml'), 'w') as fh:
+            fh.write(
+                textwrap.dedent("""
+                [build-system]
+                requires = ["setuptools"]
+                build-backend = "setuptools.build_meta"
+                """)
+            )
+        self.assertFalse(project.verify_pyproject_toml(root))
+        self.assertIn(
+            "pyproject.toml has invalid 'build-system.build-backend'. "
+            "Expected 'pbr.build'; got 'setuptools.build_meta'",
+            self.stderr.getvalue(),
+        )
+
+    def test_missing_project_table(self):
+        root = self.useFixture(fixtures.TempDir()).path
+        with open(os.path.join(root, 'pyproject.toml'), 'w') as fh:
+            fh.write(
+                textwrap.dedent("""
+                [build-system]
+                requires = ["pbr>=6.0.0", "setuptools>=64.0.0"]
+                build-backend = "pbr.build"
+                """)
+            )
+        self.assertTrue(project.verify_pyproject_toml(root))
+        self.assertIn(
+            "pyproject.toml is missing 'project' table",
+            self.stderr.getvalue(),
+        )
+
+
 class TestProjectExtras(testtools.TestCase):
     def test_pyproject_toml(self):
         root = self.useFixture(fixtures.TempDir()).path

playbooks/files/project-requirements-change.py

@@ -126,6 +126,14 @@ def main():
             backports = {}
 
         cwd = os.getcwd()
+
+        # Verify that pyproject.toml is present and contains the required
+        # attributes. We only do this on master since we don't want to be
+        # strict on already released branches
+        pyproject_found = None
+        if branch in ('master', 'main'):
+            pyproject_found = project.verify_pyproject_toml(cwd)
+
         # build a list of requirements in the proposed change,
         # and check them for style violations while doing so
         head_proj = project.read(cwd)
@@ -149,8 +157,14 @@ def main():
         )
 
     # report the results
+    error = False
     if failed or head_reqs.failed:
         print("*** Incompatible requirement found!")
+        error = True
+    if pyproject_found is False:
+        print("*** Invalid or missing pyproject.toml!")
+        error = True
+    if error:
         print("*** See https://docs.openstack.org/requirements/latest/")
         sys.exit(1)